Rtos API example

Revision:
0:9fca2b23d0ba
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mbed-os/rtos/Thread.cpp	Sat Feb 23 12:13:36 2019 +0000
@@ -0,0 +1,388 @@
+/* mbed Microcontroller Library
+ * Copyright (c) 2006-2012 ARM Limited
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+#include "rtos/Thread.h"
+
+#include "mbed.h"
+#include "rtos/rtos_idle.h"
+#include "mbed_assert.h"
+
+#define ALIGN_UP(pos, align) ((pos) % (align) ? (pos) +  ((align) - (pos) % (align)) : (pos))
+MBED_STATIC_ASSERT(ALIGN_UP(0, 8) == 0, "ALIGN_UP macro error");
+MBED_STATIC_ASSERT(ALIGN_UP(1, 8) == 8, "ALIGN_UP macro error");
+
+#define ALIGN_DOWN(pos, align) ((pos) - ((pos) % (align)))
+MBED_STATIC_ASSERT(ALIGN_DOWN(7, 8) == 0, "ALIGN_DOWN macro error");
+MBED_STATIC_ASSERT(ALIGN_DOWN(8, 8) == 8, "ALIGN_DOWN macro error");
+
+static void (*terminate_hook)(osThreadId_t id) = 0;
+extern "C" void thread_terminate_hook(osThreadId_t id)
+{
+    if (terminate_hook != (void (*)(osThreadId_t))NULL) {
+        terminate_hook(id);
+    }
+}
+
+namespace rtos {
+
+void Thread::constructor(osPriority priority,
+        uint32_t stack_size, unsigned char *stack_mem, const char *name) {
+
+    const uintptr_t unaligned_mem = reinterpret_cast<uintptr_t>(stack_mem);
+    const uintptr_t aligned_mem = ALIGN_UP(unaligned_mem, 8);
+    const uint32_t offset = aligned_mem - unaligned_mem;
+    const uint32_t aligned_size = ALIGN_DOWN(stack_size - offset, 8);
+
+    _tid = 0;
+    _dynamic_stack = (stack_mem == NULL);
+    _finished = false;
+    memset(&_obj_mem, 0, sizeof(_obj_mem));
+    memset(&_attr, 0, sizeof(_attr));
+    _attr.priority = priority;
+    _attr.stack_size = aligned_size;
+    _attr.name = name ? name : "application_unnamed_thread";
+    _attr.stack_mem = reinterpret_cast<uint32_t*>(aligned_mem);
+}
+
+void Thread::constructor(Callback<void()> task,
+        osPriority priority, uint32_t stack_size, unsigned char *stack_mem, const char *name) {
+    constructor(priority, stack_size, stack_mem, name);
+
+    switch (start(task)) {
+        case osErrorResource:
+            error("OS ran out of threads!\n");
+            break;
+        case osErrorParameter:
+            error("Thread already running!\n");
+            break;
+        case osErrorNoMemory:
+            error("Error allocating the stack memory\n");
+        default:
+            break;
+    }
+}
+
+osStatus Thread::start(Callback<void()> task) {
+    _mutex.lock();
+
+    if ((_tid != 0) || _finished) {
+        _mutex.unlock();
+        return osErrorParameter;
+    }
+
+    if (_attr.stack_mem == NULL) {
+        _attr.stack_mem = new uint32_t[_attr.stack_size/sizeof(uint32_t)];
+        MBED_ASSERT(_attr.stack_mem != NULL);
+    }
+
+    //Fill the stack with a magic word for maximum usage checking
+    for (uint32_t i = 0; i < (_attr.stack_size / sizeof(uint32_t)); i++) {
+        ((uint32_t *)_attr.stack_mem)[i] = 0xE25A2EA5;
+    }
+
+    memset(&_obj_mem, 0, sizeof(_obj_mem));
+    _attr.cb_size = sizeof(_obj_mem);
+    _attr.cb_mem = &_obj_mem;
+    _task = task;
+    _tid = osThreadNew(Thread::_thunk, this, &_attr);
+    if (_tid == NULL) {
+        if (_dynamic_stack) {
+            delete[] (uint32_t *)(_attr.stack_mem);
+            _attr.stack_mem = (uint32_t*)NULL;
+        }
+        _mutex.unlock();
+        _join_sem.release();
+        return osErrorResource;
+    }
+
+    _mutex.unlock();
+    return osOK;
+}
+
+osStatus Thread::terminate() {
+    osStatus_t ret = osOK;
+    _mutex.lock();
+
+    // Set the Thread's tid to NULL and
+    // release the semaphore before terminating
+    // since this thread could be terminating itself
+    osThreadId_t local_id = _tid;
+    _join_sem.release();
+    _tid = (osThreadId_t)NULL;
+    if (!_finished) {
+        _finished = true;
+        ret = osThreadTerminate(local_id);
+    }
+    _mutex.unlock();
+    return ret;
+}
+
+osStatus Thread::join() {
+    int32_t ret = _join_sem.wait();
+    if (ret < 0) {
+        return osError;
+    }
+
+    // The semaphore has been released so this thread is being
+    // terminated or has been terminated. Once the mutex has
+    // been locked it is ensured that the thread is deleted.
+    _mutex.lock();
+    MBED_ASSERT(NULL == _tid);
+    _mutex.unlock();
+
+    // Release sem so any other threads joining this thread wake up
+    _join_sem.release();
+    return osOK;
+}
+
+osStatus Thread::set_priority(osPriority priority) {
+    osStatus_t ret;
+    _mutex.lock();
+
+    ret = osThreadSetPriority(_tid, priority);
+
+    _mutex.unlock();
+    return ret;
+}
+
+osPriority Thread::get_priority() {
+    osPriority_t ret;
+    _mutex.lock();
+
+    ret = osThreadGetPriority(_tid);
+
+    _mutex.unlock();
+    return ret;
+}
+
+int32_t Thread::signal_set(int32_t flags) {
+    return osThreadFlagsSet(_tid, flags);
+}
+
+Thread::State Thread::get_state() {
+    uint8_t state = osThreadTerminated;
+
+    _mutex.lock();
+
+    if (_tid != NULL) {
+#if defined(MBED_OS_BACKEND_RTX5)
+        state = _obj_mem.state;
+#else
+        state = osThreadGetState(_tid);
+#endif
+    }
+
+    _mutex.unlock();
+
+    State user_state;
+
+    switch(state) {
+        case osThreadInactive:
+            user_state = Inactive;
+            break;
+        case osThreadReady:
+            user_state = Ready;
+            break;
+        case osThreadRunning:
+            user_state = Running;
+            break;
+#if defined(MBED_OS_BACKEND_RTX5)
+        case osRtxThreadWaitingDelay:
+            user_state = WaitingDelay;
+            break;
+        case osRtxThreadWaitingJoin:
+            user_state = WaitingJoin;
+            break;
+        case osRtxThreadWaitingThreadFlags:
+            user_state = WaitingThreadFlag;
+            break;
+        case osRtxThreadWaitingEventFlags:
+            user_state = WaitingEventFlag;
+            break;
+        case osRtxThreadWaitingMutex:
+            user_state = WaitingMutex;
+            break;
+        case osRtxThreadWaitingSemaphore:
+            user_state = WaitingSemaphore;
+            break;
+        case osRtxThreadWaitingMemoryPool:
+            user_state = WaitingMemoryPool;
+            break;
+        case osRtxThreadWaitingMessageGet:
+            user_state = WaitingMessageGet;
+            break;
+        case osRtxThreadWaitingMessagePut:
+            user_state = WaitingMessagePut;
+            break;
+#endif
+        case osThreadTerminated:
+        default:
+            user_state = Deleted;
+            break;
+    }
+
+    return user_state;
+}
+
+uint32_t Thread::stack_size() {
+    uint32_t size = 0;
+    _mutex.lock();
+
+    if (_tid != NULL) {
+        size = osThreadGetStackSize(_tid);
+    }
+
+    _mutex.unlock();
+    return size;
+}
+
+uint32_t Thread::free_stack() {
+    uint32_t size = 0;
+    _mutex.lock();
+
+#if defined(MBED_OS_BACKEND_RTX5)
+    if (_tid != NULL) {
+        os_thread_t *thread = (os_thread_t *)_tid;
+        size = (uint32_t)thread->sp - (uint32_t)thread->stack_mem;
+    }
+#endif
+
+    _mutex.unlock();
+    return size;
+}
+
+uint32_t Thread::used_stack() {
+    uint32_t size = 0;
+    _mutex.lock();
+
+#if defined(MBED_OS_BACKEND_RTX5)
+    if (_tid != NULL) {
+        os_thread_t *thread = (os_thread_t *)_tid;
+        size = ((uint32_t)thread->stack_mem + thread->stack_size) - thread->sp;
+    }
+#endif
+
+    _mutex.unlock();
+    return size;
+}
+
+uint32_t Thread::max_stack() {
+    uint32_t size = 0;
+    _mutex.lock();
+
+    if (_tid != NULL) {
+#if defined(MBED_OS_BACKEND_RTX5)
+        os_thread_t *thread = (os_thread_t *)_tid;
+        uint32_t high_mark = 0;
+        while (((uint32_t *)(thread->stack_mem))[high_mark] == 0xE25A2EA5)
+            high_mark++;
+        size = thread->stack_size - (high_mark * sizeof(uint32_t));
+#else
+        size = osThreadGetStackSize(_tid) - osThreadGetStackSpace(_tid);
+#endif
+    }
+
+    _mutex.unlock();
+    return size;
+}
+
+const char *Thread::get_name() {
+    return _attr.name;
+}
+
+int32_t Thread::signal_clr(int32_t flags) {
+    return osThreadFlagsClear(flags);
+}
+
+osEvent Thread::signal_wait(int32_t signals, uint32_t millisec) {
+    uint32_t res;
+    osEvent evt;
+    uint32_t options = osFlagsWaitAll;
+    if (signals == 0) {
+        options = osFlagsWaitAny;
+        signals = 0x7FFFFFFF;
+    }
+    res = osThreadFlagsWait(signals, options, millisec);
+    if (res & osFlagsError) {
+        switch (res) {
+            case osFlagsErrorISR:
+                evt.status = osErrorISR;
+                break;
+            case osFlagsErrorResource:
+                evt.status = osOK;
+                break;
+            case osFlagsErrorTimeout:
+                evt.status = (osStatus)osEventTimeout;
+                break;
+            case osFlagsErrorParameter:
+            default:
+                evt.status = (osStatus)osErrorValue;
+                break;
+        }
+    } else {
+        evt.status = (osStatus)osEventSignal;
+        evt.value.signals = res;
+    }
+
+    return evt;
+}
+
+osStatus Thread::wait(uint32_t millisec) {
+    return osDelay(millisec);
+}
+
+osStatus Thread::yield() {
+    return osThreadYield();
+}
+
+osThreadId Thread::gettid() {
+    return osThreadGetId();
+}
+
+void Thread::attach_idle_hook(void (*fptr)(void)) {
+    rtos_attach_idle_hook(fptr);
+}
+
+void Thread::attach_terminate_hook(void (*fptr)(osThreadId_t id)) {
+    terminate_hook = fptr;
+}
+
+Thread::~Thread() {
+    // terminate is thread safe
+    terminate();
+    if (_dynamic_stack) {
+        delete[] (uint32_t*)(_attr.stack_mem);
+        _attr.stack_mem = (uint32_t*)NULL;
+    }
+}
+
+void Thread::_thunk(void * thread_ptr)
+{
+    Thread *t = (Thread*)thread_ptr;
+    t->_task();
+    t->_mutex.lock();
+    t->_tid = (osThreadId)NULL;
+    t->_finished = true;
+    t->_join_sem.release();
+    // rtos will release the mutex automatically
+}
+
+}